code: def plot_frame(label=None):
      plt.close()
      plt.title("8th-order Chebyshev coefficient convergence")
      plt.xlabel("Differential Evolution %s" % label)
      plt.ylabel("Chi-Squared")
      plt.draw()
      plt.pause(0.001)
      return
  
file_path: mystic/examples/example10.py
imports: from mystic.solvers import DifferentialEvolutionSolver2
  from mystic.models.poly import chebyshev8, chebyshev8cost
  from mystic.models.poly import chebyshev8coeffs
  from mystic.termination import VTR
  from mystic.strategy import Best1Exp
  from mystic.monitors import VerboseMonitor, Monitor
  from mystic.tools import getch, random_seed
  from mystic.math import poly1d
  import matplotlib.pyplot
label_desc: Use image node_id 1 for calling a global function with example usage: plot_frame(label) without return types